Motor driven headstock for machine tools



March 22, 1938. A. w. WIGGLESWORTH 2,

MOTOR DRIVEN HEADSTOCK FOR MACHINE TOOLS Original Filed Sept. 8, 1936 2Sheets-Sheet 1 I i ,3] 12+ 3 l j] i I 14 3 i ZTI f\ I I l I Q I M I l 540/5 i -z Z Z 53 2 7 fizfezgfoi.

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Max-ch22, 19386 A. w. WIGGLESWORTH ,1

MOTOR DRIVEN HEADSTOCK FOR MACHINE TOOLS Original Filed Sept. 8, 1936 2Sheets-Sheet 2 This object is best accomplished belts be kept free ofgrease and oil,

r med Mar. 22, 1938 UNITED STATES MOTOR DRIVEN HEADSTOOK FOR MACHINE;TooLs Albert w. wiggitswoith, Chicago, Iii, assign'or to ,Hill-ClarkeMachinery 00., Chicago, 11]., a cornotation of Illinois Originalapplication September 8', 1936, Serial No.

Divided, and this application January 11, 1937, Serial No. 119,919

4 claims. (oi. 82--28) This invention relates to motor driven had stocksfor machine tools, such as grinding inaohines and the like.

The main object of the invention is to provide operative connectionsbetween the motor and the work engaging member whereby vibration issubstantially eliminated and perfectly smooth surfaces are imparted tothe work being machined. by providing a belt drive for rotating the workengaging member. Preferably a rubber belt or a plurality of rubber beltsare used. Since oil deleteriously affects rubber, it, is essential thatthe belt or and, therefore, an object of the invention is to provideoilless bearings for the belt-driven mechanism. Such oilless bearingsare injuriously affected by the water used in the operation of somemachine tools, such as grinding machines and the like,

and, therefore, another object of the invention is to provide means forpreventing water from entering the housing which preferably encloses thedriving mechanism or from otherwise coming in contact with saidbearings.

This application is a division of my application Serial No. 99,761,filed September 8, 1936. 'In the drawings: Fig. 1 is a transverse,vertical sectional view, partly in elevation, taken in the plane of theline l--| of Fig. 2. V I v Fig, 2 is a horizontal sectional view takenin the plane of the broken line 2--2 of Fig. 1. v Fig. 3 is an enlargedvertical sectional view taken in the plane of the line 3-3 of Fig. 2,with the center head removed. I Y Fig. 4 isa transverse, verticalsectional view, partly in elevation, taken in the plane of the line 4-4of Fig. 3. I p p In that embodiment of my invention shownin thedrawings, a, work carriage H is longitudinally slidable on a base, notshown. On one-end of the carriage I! is carried a' headstock whichcooperates with a tailstock, not shown, to support the work. 7 V

The headstock comprises a lower housing consisting of a stationary partl2, and movable parts i3 and l3, two supports I4, |4 connected tothepart E2 of the housing, and a two-piece upper housing I on the supportsl4. In the upper housing l5 are mounted a motor l6, pulley supportingframe l1, and a grooved pulley I8 and plain wide pulley I9 on ashaft 20.motor 16 is fixedly mounted on the floor 2| which partially closes thebottom of the housing l5.

Spaced apart brackets 22 on the floor 2| support a horizontal shaft 23on which is pit orally indunt of the frame I! ends for the. reception ofthe pulley shaft ro- The upwardly curved 24 are apertured at theiriipper ed the frame I1.

tatably mounted therein. The pulley I8 is fixed on one end of the shaft20 and the wide pulley i9 is fixed to said shaftbetween the arms 24. ofthe frame One of the arms of the frame I! is extended beyond the shaft23 as indicated at 25 and is apertured to receive an adjusting screw 26.A depending lug 27 on said arm is apertured for the reception of anadjusting screw 28. The adjustment of the screws 26 and 28 in the end 25and lug bearing on the floor 2| of the housing, swings the frame |1relatively to the shaft 23 and thus varies the position of the pulleyill for the purpose of adjusting the tension pulle l8 to shaft 20, abelt 3| on the wide pulley |9 on said shaft 2|l extends through the openbottom of the housing |5 and transmits power to the drive shaft 32through the speedchange pulley 33 on said shaft 32. The shaft 32 isoperatively connected with a workdriver 34 by operative connectionshereinafter described.

headstock center is indicated at 35.

Speed change is accomplished by moving the belt 3| longitudinally of thewide pulley I9 and stepped or cone pulley 33. In order to permit thebelt 3| to be moved, it is necessary to relieve the belt 3| of tensionand this is accomplished by pressing downwardly on rigidly connected tothe part 31 of the housing l3, said housing l3 and arm 38 beingpivotally mounted to rotate about the hollow center head shaft 39 whichis in alignment with the center 35. The arm 38 terminates in a bearingfor the shaft 32. The downward actuation of the lever 36 and pivotalmovement of the arm 38 (the latter being pivotally connected with shaft32), raises the shaft 32, housing 3 and the changespeed pulley 33 andrelieves the belt 3| of tension, so that it may be moved on the pulleysI9 and 33 to vary the speed of the shaft 32. When the lever 36 isreleased after adjustment of the belt 3| on pulleys H] and 33, thepulley 33 with shaft 32 and associated-housing l3 move by gravity to theposition shown in Figs. 1 and 2 in which the belt 3| is under propertension for operating purposes.

Referring to the operative connections between the shaft 32 and the workdriver 34, one end of the shaft 32 is mounted in an oilless bearing 40in the housing I3. Said shaft end carries a pulley 4| which, preferably,is a multi-grooved type pulley, connected by a plurality of belts 42 toa pulley 43. The pulley 43 has an integral elongated bearing sleeve 44which surrounds an oilless bearing 45 on the hollow center head shaft 39in. which the center 35 is mounted.v In the present embodiment thecenter 35 is stationary andthe work driver 34 is rotated about the shaft39, but obviously the center 35 could be rotata lever 36 which is ablyconnected if desired. The work driver 34 is secured by bolts 46 to thepulley 43. A flat apertured disc All is secured to the end of the shaft39 by bolts 48 for retaining an oilless washer 49 in place adjacent theforward ends of the pulley sleeve M and bearing 45. Another oillesswasher 5!! ends of the bearing 45 and pulley sleeve A i and an offsetshoulder formed in the sleeve 5! which houses the shaft 39 and is partof the fixed housing I2. A bearing 52 is located between the pulleysleeve 14 and the sleeve 5|, and between the pulley sleeve 44 and amember 53 which moves with the movable housing l3--l 3'.

' In the present embodiment the pulley 43 with its sleeve 44 andconnected work driver 34 rotate about the fixed shaft 39. Normally,during such operation, the housing 13 and member 53 are stationary butwhen it is desired to change the speed of the shaft 32, the lever 35 maybe depressed, whereby the arm 38 and housing I3-l3 with member 53 arepivotally moved about the shaft 39 and sleeve El and about the bearing52, thereby lifting the drive shaft 32 and change speed pulley 33 topermit movement of the belt 3! on the pulley 33.

The belts 42 preferably are held under proper adjustable tension on thepulleys ii and 43 by means more fully described in the application ofwhich this is a division. As shown in Fig. 1, a stub shaft 54 is rigidlysecured to the housing 13, and has pivotally mounted on it an arm 55which carries an idler pulley 56, for bearing on the belt or belts 42.

All the bearings in the housing i3-l3 are oilless, as heretoforedescribed, and thus the rubber belt or belts 42, which I preferably use,cannot be deleteriously affected by oil. However, to avoid injury to theoilless bearings, contact with moisture must be avoided, and to this endmeans for preventing water from entering the housing or otherwisecontacting the bearings are provided.

Said means are best shown in Figs. 3 and 4, in which the work driver 3Qis shown in two vertical sectional views at right angles to each other,and with the center head 35 removed. Water is most likely to enter thehousing through the opening 51 which is partially closed by the head 35.Said opening communicates with an annular space 58 between the workdriver 34 and the forward part of the pulley sleeve 44, the disc Q1 andouter edge of the washer 49. The work driver 34 has a plurality ofradially extending passageways 59 in its body, communicating with saidannular space 58, and extending to the peripheral edge 60 of the workdriver. The edge 60 fits within the inwardly directed flange SI of thehousing l3, but the annular space 62 between the work driver edge Giland housing flange BI is sufficient to allow water to pass from thepassageways 5% through said space 62 to a recess 63 in the housing l3and thence out through the slot 64, or to pass from the passageways 59through the space 62 and out through the peripheral recess 65 in thework driver. It will be noted that the flange 66 on the face of the part6| of the housing I8 is cut way at the lower part of said housing sothat water which may enter the opening 57 in the housing may pass outthrough the surface 'of the groove or recess 65 without interferenceby'the flange 66. By providing the communicating passageways 58, 59, 62,leading out through 63 and 64 or 65, moisture is kept away from theoilless bearings in the driving mechanism, and injury to is interposedbetween the other.

said bearings is avoided. Thus I am enabled to use a rubber belt orbelts to drive the pulley 43 and attached work driver 34 withoutsubjecting such belt or belts to oil or grease which would render themuseless in a very short time.

In Fig. 3 is shown a bolt 61 with square head 68 located in one of twoslots 69 in the face of the work driver, for use in connecting the workto said member.

Of course, it will be understood that either or both of the pulleys 4|and 43 may be grooved or plain, and that a single or multi-belt drivemay be used.

The elimination of gears and provision of the driving means hereindescribed enable the machine to produce exceptionally smooth work.

Changes may be made in details of construction without departing fromthe scope of my invention and I do not intend to be limited to the exactform shown and described, except as set forth in the appended claims.

I claim:-

1. A motor driven head stock comprising a housing, a center head shaftin the housing, a rotatable work driver, means on the shaft for drivingthe work engaging member, and means for preventing water from enteringthe housing, said means comprising a plurality of passageways in thework driver extending from its axial portion to a peripheral recesslocated in the edge of the work driver externally of the housing.

2. A motor driven head stock comprising a housing, a center head shaftin the housing, a centrally apertured, rotatable work driver, means onthe shaft for driving the work driver, and means for preventing waterfrom entering the housing through said aperture in the work driver, saidmeans comprising a plurality of passageways in the work driver extendingfrom its axial portion to its peripheral edge, an annular space betweenthe housing wall and work driver, and a slot in the lower part of thehousing wall communicating with said annular space for permitting waterto pass out without entering the interior of the housing.

3. A motor driven headstock comprising a housing, a center head shaft inthe housing, a rotatable work driver and pulley on the shaft, an oillessbearing between the pulley and the center head shaft in the housing,means including a rubber belt for driving said pulley and means forpreventing water from entering the housing and from contacting saidoilless bearing, said means comprising a plurality of passageways in thework driver extending from its axial portion to a peripheral recesslocated in the edge of the work driver externally of the housing.

4. A motor driven headstock comprising a housing, a center head shaft inthe housing, a rotatable work driver and pulley on the shaft, an oillessbearing between the pulley and the center head shaft in the housing,means including a rubber belt for driving said pulley and means forpreventing water from entering the housing and from contacting saidoilless bearing, said means comprising a plurality of passageways in thework driver extending from its axial portion to its peripheral edge, anannular space between the housing wall and the work driver, and a slotin the lower part of the housing wall communicating with said annularspace for permitting water to pass out without entering

